You know the final scene of the 2007 Disney movie Ratatouille, when the rat cooks up an amazingly inspired reinterpretation of a classic ratatouille, transforming the humble summer vegetable stew into a gorgeous layered construction that melts a bitter restaurant critic's heart? Wasn't it wonderful? And didn't it then inspire an endless rash of internet recipes, each attempting to re-create the movie's "ratatouille" for everyone to make at home?
Well, I have an issue with all of that, because as far as I'm concerned, the dish in the movie isn't ratatouille, no matter how you slice it—or, actually, specifically because of how you slice it and then cook it.
As the story goes, Thomas Keller, who consulted on the film, offered his fancy layered "ratatouille" recipe as the pièce de résistance for that final scene; he called it a byaldi. Keller's byaldi, meanwhile, can be traced back to the French chef Michel Guérard, one of the founders of nouvelle cuisine, who named it after a Turkish stuffed eggplant dish.
Here's the problem: That upgraded ratatouille traveled an unnecessarily convoluted path through the hands of two famous chefs and one Disney movie, because it already existed in Provence, sitting right alongside ratatouille on the dinner table. It's been made there for generations, and any restaurant critic worth his salt would have recognized it for what it was right away—not ratatouille, but a tian.
Technically, a tian is any casserole cooked in an earthenware vessel by the same name, but these days it almost always refers to some kind of layered vegetable dish that's gratinéed (browned on top) in the oven. Zucchini and other squash are very common in tians, as are eggplant and tomato. (Notice the overlap with ratatouille ingredients...but, still, doesn't make it ratatouille.) And they're often made very much like you see in the movie, with some kind of sauce in the casserole and raw, thinly sliced vegetables either tossed in the sauce or layered on top, then baked until the vegetables are tender.
But my problem with the dish isn't just a semantic one. I also have issues with the overall method of cooking the dish, because it almost always ends up with the vegetables tasting bland. That shouldn't be much of a surprise—what else is going to happen when watery vegetables are crowded together in a dish and then baked in a steamy cloud of each other's moisture?
So, not only do I want to restore this dish to its proper name—a tian—I also want to improve how this particular tian tastes, making sure that the flavors end up concentrated and intense, not watery and bland.
The obvious fix is to pre-cook each vegetable individually to get rid of some of the excess moisture before layering them together. Plus, pre-cooking means we can better develop their flavors by browning each piece, which is almost impossible when they're steaming away in the oven.
I played with a couple of ways to do that. I was sure the easiest would be to toss each sliced vegetable with oil, spread them in a single layer on baking sheets, and roast them in the oven, but that didn't work well at all: When sliced thinly, vegetables like squash and eggplant dehydrate in the oven long before they brown.
I tried pre-salting the eggplant and squashes to drive off some excess moisture before putting them in the oven. But those thin slices absorb way too much salt, and, since they're the bulk of the final dish, it ends up horribly salty.
Ultimately, I found that the best method was to sauté each sliced vegetable in a very hot skillet, working in batches small enough to guarantee that they'd brown before they risked overcooking and turning to mush. I also found that the ideal slice thickness is somewhere between one-eighth and one-quarter of an inch—any thinner, and the slices shrink to almost nothing as they cook, making them incredibly difficult to work with later.
It takes a little time to do this, but not too much, and the flavor improvement is well worth it. As each batch finished, I transferred it to a baking sheet, spreading the vegetables in an even layer to cool. As you can see, the OCD side of me took over—I couldn't resist the urge to re-stack each vegetable after it had cooled, which actually made them really easy to work with later.
With the vegetables cooked, I whipped up a quick tomato sauce, then spooned it into the bottom of an earthenware casserole. Mine has about a two-quart capacity, but there's some flexibility on the necessary volume and shape of the baking vessel. Just arrange the vegetables in a way that works, packing them more tightly if the dish is smaller and spacing them apart more if it's bigger.
If your dish is round, a circular pattern, like what I used here, works well; if it's rectangular, you may want to do rows instead.
Then I spooned a little more sauce on top, popped the dish in a hot oven, and cooked it until it was heated through. I didn't worry too much about browning the top of the casserole here, since I'd already browned all my vegetable slices beforehand.
Because the vegetables had a head start on cooking, they reduced and intensified in flavor in the oven, becoming creamy and getting a nice balance of bright flavors and sweetness from the browning. If I were to describe the result, I'd say it was like the love child of Italian eggplant parm and, well, ratatouille. That's a far better background story, anyway.